Parse a file, replace a particular strings and save new file

waytoperl has asked for the wisdom of the Perl Monks concerning the following question:

I'm new to perl and want to write my first perl code, that will be used in a project. Problem: I've a file, "FileName.lib". Need to replace "values" with 500 for string_name500(Transition_11) and with 100 for string_name100(Transition_11). After replace, I need to save updated file with NewFileName.lib Please help me. these file consists -->

string_name500(Transition_11) {
values ( \
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ");
+ 

string_name100(Transition_11) {
values ( \
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ",\
"0, 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008 ");
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Comment on Parse a file, replace a particular strings and save new file Download Code

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Re: Parse a file, replace a particular strings and save new file by NetWallah (Canon) on Nov 13, 2013 at 05:16 UTC
Welcome to the Monastery. The following code solves your problem as specified. If it does not do what you WANT, you need to improve your specification. `perl -pe '$x++ ? s/\bvalues\b/100 for string_name100(Transition_11)/ : s/\bvalues\b/500 for string_name500(Transition_11)/ ' FileName.lib > NewFileName.lib` [download] Of course, it would help if you showed us what you TRIED, and explain what you have trouble with. Please read How do I post a question effectively?. When in doubt, mumble; when in trouble, delegate; when in charge, ponder. -- James H. Boren	[reply] [d/l]
Re: Parse a file, replace a particular strings and save new file by davido (Cardinal) on Nov 13, 2013 at 08:09 UTC
How have you come to be a code contributor on a Perl project without first having a working knowledge of Perl? Rather than doing your project for you, we should be assisting you in gaining sufficient proficiency in Perl to accomplish this trivial task yourself. So where can we start? I suggest spending 20 to 30 minutes with perlintro. Then follow some of the links in that document to dive deeper into file IO, and regular expressions. An hour or two later you'll be competent to solve this, and many future problems yourself. And when you do come up with stumbling blocks in the future (as we all do), you'll be equipped with enough understanding of the Perl basics to be able to ask informed questions. Dave	[reply]
Re: Parse a file, replace a particular strings and save new file by ig (Vicar) on Nov 13, 2013 at 06:15 UTC
You might find Getting Started with Perl helpful. There are references to many resources there.	[reply]
Re^2: Parse a file, replace a particular strings and save new file by sanku (Beadle) on Nov 13, 2013 at 09:36 UTC
Hi, Try this code `my ($v1,$value,$i); open (FILE,"old.txt") or die $!; open (NEW,">new.txt") or die $!; while(<FILE>){ if($_ =~/string_/){ ($v1, $v2) = split(/name/,$_); ($value) = split(/\(/,$v2); } $_ =~s/values/$value/; print NEW $_; } ~` [download]	[reply] [d/l]